expstr
expsize = exponent(expstr, expt - 1, expchar);
PRINT(expstr, expsize);
CHAR_T expstr[MAXEXPDIG+2]; /* buffer for exponent string: e+ZZZ */
ttoa(expstr, sizeof expstr, pw->pw_expire));
char chgstr[256], expstr[256];
expstr(nl->n_name);
expstr(expbuf);
expstr(expbuf);
static void expstr(char *);